An unintentional prank, and I was a witness rather than a participant.
One of the machines on the shop floor had broken down and a fitter and technician were in the process of fixing it. While the technician was underneath it checking the wiring, the fitter saw that the air dump valve was still closed and released it without first warning the technician. The machine depressurised and released the air from all the mechanisms at once, through an outlet about two inches from the technician's head.

The technician, cool as you like, just came up from underneath the machine and said to the fitter, "Here Kev, can you give me a shave as well as a haircut?"
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Tue 13 Mar 2012, 15:54, 1 reply, 13 years ago)

I would've shit myself

( Lisette von Falcon, Tue 13 Mar 2012, 15:57, Reply)